The present invention relates to photographic recording devices for the recording of photographic images onto a medium, especially onto a band-shaped medium. The invention relates in particular to drum recording devices wherein a band-shaped medium is clamped on a drum for the recording of photographic images onto the band-shaped medium.
Such a drum recording device is known from EP 1 009 158 A1.
The recording device known from EP 1 009 158 A1 is shown in FIG. 18. The recording device includes as clamping arrangement a clamping drum 1100 as first holding mechanism a fastening means 1160 for the fastening of a recording medium M onto the mantle 1110 of the clamping drum and a recording unit 1200 stationary relative to the direction of rotation of the clamping drum. The recording unit 1200 records onto the recording medium imaging information which is supplied thereto in the form of electrical signals, which medium is fastened onto the mantle of the rotating clamping drum 1100. Mounting means 1120 or a roll 1130 functioning as a medium source are provided in the interior of the clamping drum 1100, onto which a supply of recording medium M is wound into a roll. The clamping drum 1100 includes in its mantle 1110 a break in the clamping track in the form of a slit 1140 through which the recording medium M is first guided from the interior of the clamping drum 1100 onto its mantle 1110 and then fastened thereon.
The fastening means are constructed as a clamping arrangement which includes two carrier arms, 1161 and 1162 positioned closely to the two sides of the mantle 1110 and a clamping bar 1163 connecting them. The clamping bar extends transverse over the width of the clamping track or the clamping drum 1100. A knife bar 1170 is also mounted on the two carrier arms 1161, 1162 and extends transverse to the mantle 1110. It functions as a cutting device. The knife bar is moveable together with the clamping bar 1163. The clamping bar 1163 is biased against the surface of the mantle 1110 by not illustrated springs and thereby clamps the recording medium M positioned thereunder onto the mantle 1110 of the clamping drum 1100.
An actuating device 1180 is provided opposite the recording unit 1200 and stationary in a not illustrated frame. The actuating arrangement is controlled by the control 1300 and activates the clamping arrangement 1160 and the cutting arrangement 1170, when the clamping drum 1100 is in a predefined rotational position in which the actuating arrangement 1180 is opposite the clamping arrangement 1160 and can be brought into engagement therewith. At the same location and also stationary in a not illustrated frame is provided a drive arrangement 1190 which in the mentioned rotational position of the clamping drum 1100 is brought into contact with the recording medium M on the mantle 1110 under the control of the control 1300 and provides for the advancement of the recording medium M in direction of rotation of the clamping drum 1100 relative to the mantle 1110.
As shown in the detailed illustration of FIG. 19, the drive arrangement 1190 essentially includes a drive roller 1192 rotatably mounted in a pivotable frame 1191 which is driven by a motor 1194 connected with a control 1300 and by way of a belt 1193. The pivotable frame 1191 is mounted stationary in a not illustrated frame and can be moved to and from the mantle 1110 by way of an only symbolically illustrated excenter mechanism 1195-1196, whereby the drive roller 1192 is brought into contact with the recording medium M supported on the mantle or is lifted off therefrom. The clamping arrangement 1160 and the cutting arrangement 1170 connected therewith are also operated by the same excenter mechanism 1195-1196. The excenter mechanism 1195-1196 is driven by another not illustrated stationary motor which in turn is connected with the control 1300 and controlled thereby.
The function of the recording device is as follows.
After the fastening of the storage roller 1130 of recording medium M onto the clamping pin 1120 in the interior of the clamping drum 1100, the start of the band shaped recording medium M is manually guided between the clamping roller pair 1152-1153 through the slit 1140 to the outside, around the mantle 1110 of the clamping drum 1100 and clamped down by the clamping arrangement 1150. The drive arrangement 1190 is in an inactive position in which the drive roller 1192 is lifted off the mantle 1110. In this manner, the recording medium M is clamped on the clamping drum 1100 and the device is ready for the recording procedure (FIG. 19).
The clamping drum 1100 is now rotated in direction of the arrow D together with the recording medium M and the image information to be recorded is recorded in a known manner by way of the recording unit 1200 onto the section of the recording medium M located on the mantle 1110 or under a part thereof. When the recording process is finished, the clamping drum is stopped in the above mentioned, defined rotational position (park position).
As illustrated in FIG. 20, the drive arrangement 1190 is now lowered onto the mantle 1110 so that the drive roller 1192 comes into contact with the recording medium M on the mantle. At the same time or immediately thereafter, the clamping arrangement 1160 together with the knife bar 1170 are lifted off the mantle 1110 so that the recording medium M is at this location held against the mantle 1110 only by the drive roller 1192.
The printed (image carrying) portion of the recording medium M is now ejected (FIG. 21). For this purpose, the drive roller 1192 is rotated and the recording medium band M advanced in the rotational direction of the clamping drum 1100 under and past the knife bar 1170 until the rear end of the printed portion is located under the knife bar 1170.
The clamping arrangement 1160 together with the knife bar 1170 connected therewith is thereafter pressed against the mantle 1110 and at the same time or immediately thereafter the drive arrangement 1190 is lifted off the mantle 1110. By way of the downwards movement (relative to the drum radially inward) of the clamping arrangement 1160 and the knife beam 1170, the printed portion of the medium is cut off and the new front end of the still unprinted medium is clamped onto the clamping drum. The device is now ready for the next recording process (FIG. 22).
The problem of an automatic loading or unloading is not solved in the above recording device.
It is now an object of the invention to provide a photographic recording device, which can be automatically loaded with a band-shaped medium or unloaded.
This object is achieved through a second holding mechanism which can clamp a band-shaped medium and relative to which the clamping arrangement can be moved, and a transport mechanism for transporting the band-shaped medium between the first and second holding mechanisms. A control is provided for the transfer of the band-shaped medium by operating one holding mechanism for releasing the band-shaped medium and activating the transport mechanism in a first preselected position for transporting the released band-shaped medium to the other holding mechanism.
The photographic recording device in accordance with the invention is used for the recording of photographic images onto a band-shaped medium. The band-shaped medium can be, for example, regular paper, light sensitive photographic paper, thermal paper or plastic foils etc. The recording of the photographic images onto the band-shaped medium is carried out with a recording unit suitable for the respective medium. For example, it can be an inkjet-recording unit which applies ink onto the regular paper. A recording unit can also apply toner onto regular paper, for example. The recording unit can also be constructed for the exposure of a light sensitive medium, for example, photographic paper. For this purpose the recording unit can include, for example, laser or light emitting display devices (cathode ray tubes, LCD displays). The recording unit can also apply the photographic images onto the medium by heat, for example, with a thermal head in cooperation with thermal paper.
The band-shaped medium is supplied from a medium source. The latter can be, for example, a roll from which the band-shaped medium is unwound. However, the band-shaped medium can also be present in folded condition, for example. The band-shaped medium can also be housed in a cassette.
The photographic recording device preferably includes a clamping arrangement which provides a clamping track along which the band-shaped medium can be clamped down. The clamping arrangement is preferably a clamping drum, whereby the clamping track extends especially along a circle. The advantage of a circular clamping track resides in that upon rotation of the clamping arrangement and with a stationary recording unit, a constant spacing is guaranteed between the clamped down band-shaped medium and the recording unit. However, other clamping arrangements can also be used, which, for example, provide a clamping track wherein several linear clamping sections are aligned in series. For example, a polygonal or multi-sided clamping arrangement can be realized wherein one recording unit is respectively associated with one portion of the track and can be carried along the latter for the recording of an image. Several images can be recorded in parallel thereby along the clamping track. After the parallel recording, the clamping arrangement can then be, for example, moved or rotated in order to record images on the remaining portions.
The clamping track has a beginning which is constructed to receive the band-shaped medium. The medium source and the beginning of the clamping track are positioned so that the band-shaped medium can be guided to the track beginning. The clamping track is constructed so that the band-shaped medium can be guided and clamped down along the clamping track. For example, the clamping track is constructed as a cylindrical mantle track on which the band-shaped medium can glide and which gives the band-shaped medium a circular shape during the clamping thereof. Alternatively, the clamping arrangement can form the clamping track, for example, by way of a framework whereby the band-shaped medium is tightened between the framework sections.
If several recording units are provided which are moveable independently of one another for the recording of the images, this results in the advantage that each recording unit can optimize and thus accelerate the recording process by an individual scanning process depending on the respective image data.
A first holding mechanism is preferably provided at the end of the track. This provides for the fastening of the band-shaped medium at the end of the track in order to tighten it along the clamping track. The tightening is carried out, for example, in that the band-shaped medium is transported back to the medium source or in that a loop is formed between the medium source and the start of the track until the band-shaped medium is taut.
The clamping arrangement is preferably moveable relative to the recording apparatus or several recording apparatus, preferably rotatable relative thereto, for the recording of the images on the tightened band-shaped medium in cooperation with the recording apparatus. The clamping arrangement, for example, a clamping drum, is preferably rotatably supported relative to the recording apparatus and the at least one recording apparatus is stationary. However, this can also be achieved in reverse so that the recording apparatus is moveable and the clamping arrangement is stationary. Finally, both the clamping arrangement as well as the at least one recording apparatus can be moveably supported to achieve a relative movement between the recording apparatus and the clamping arrangement for the recording of the images.
The movement of the clamping arrangement in accordance with the invention preferably also allows for the loading of the clamping arrangement with the band-shaped medium. Thus it preferably fulfills a dual function, since it is preferably used both for the recording as well as the loading.
Apart from the first holding mechanism, a second holding mechanism is preferably provided relative to which the clamping arrangement is moveable. The second holding mechanism is preferably stationary and the clamping arrangement can be moved relative to the second holding mechanism, especially rotated. The second holding mechanism is constructed to fasten a band-shaped medium. The second holding mechanism is preferably positioned on one side of the clamping track, for example, outside the clamping drum, while the medium source is positioned on the other side of the clamping track, for example in the interior of the clamping drum. The band-shaped medium preferably guidable through a break in the clamping track between the beginning and the end of the track and from the medium source to the second holding mechanism. This break can be, for example, a slit in the clamping drum. The clamping track is preferably also constructed such that the end of the track is closer to the beginning than to the middle of the track.
A transport mechanism is preferably provided, for example, a transport roller, which transfers a force onto the band-shaped medium for the transport thereof to slide it along the clamping track. The transport mechanism is positioned so that it transports the band-shaped medium between the first and second holding mechanisms, when the clamping arrangement is in a preselected position (first preselected position) relative to the second holding mechanism. The clamping arrangement is herefor moved relative to the second holding mechanism, especially rotated. In feeding direction of the band-shaped medium, the transport mechanism can preferably be brought into contact with the band-shaped medium and removed therefrom before the end of the track, especially at or in the vicinity of the first holding mechanism, especially directly at the input region of the latter for a front end of the band-shaped medium.
A control is provided in accordance with the invention. The control serves especially for the transfer of a band-shaped medium between the first and the second holding mechanisms. The control is preferably constructed in such a way that the band-shaped medium can be transferred thereby from the first holding mechanism to the second holding mechanism as well as from the second holding mechanism to the first holding mechanism. The transport mechanism is used for the transfer of the band-shaped medium and is actuated by the control in the first preselected position. In this first preselected position, the first holding mechanism, the transport mechanism and the second holding mechanism are in a preselected relative position. For the transfer, one of the two holding mechanisms is actuated to release the band-shaped medium held thereby. The control then activates the transport mechanism in order to transport the released band-shaped medium to the other of the two holding mechanisms. The transport of the band-shaped medium is preferably continued until the other of the two holding mechanisms can capture or hold the band-shaped medium.
The transport mechanism preferably can be moved away from the band-shaped medium when not used for the transporting so that the clamping arrangement can be freely moved, i.e. no contact exists between the band-shaped medium and the transport mechanism when the clamping arrangement is moved, especially rotated. The transport mechanism can be brought into contact with the band-shaped medium for the transport thereof. The transport mechanism is preferably mounted relative to the clamping arrangement such that the clamping arrangement can be moved relative to the transport mechanism, especially rotated. Especially, the transport mechanism is stationary while the clamping arrangement is rotatably constructed, for example. The transport mechanism can also be constructed so that it moves together with the clamping arrangement. However, a stationary positioning of the transport mechanism relative to the clamping arrangement is preferred in view of easier loading of the clamping arrangement as described later on, whereby the transport mechanism then can preferably be coupled with the first holding mechanism in a certain position, as will be described in more detail further below.
The clamping arrangement preferably moves about an axis, while the transport mechanism and a second holding mechanism are stationary. The width direction of the band-shaped medium is preferably at least about parallel to the axis. The clamping track is preferably guided about the axis in such a way that a track opening results intermediate the track beginning and the track end through which a band-shaped medium supplied from the medium source can be conveyed.
An internal medium conveyor is preferably provided and positioned such that it passes a band-shaped medium supplied by the medium source through the track opening. The internal medium conveyer is thereby preferably constructed such that it transports the band-shaped medium to the second holding mechanism so that the second holding mechanism can capture the band-shaped medium, when the clamping arrangement is in a certain position (second preselected position) relative to the second holding mechanism. The second preselected position preferably at least corresponds with the above already mentioned first preselected position. To achieve that, the internal medium conveyer preferably not only includes a convenient mechanism for actively transferring a transporting force onto the band-shaped medium (for example transport rollers) but also a guide which guides the transported band-shaped medium towards the second holding mechanism when the clamping arrangement is in the second preselected position. This guide is preferably constructed such that the band-shaped medium is advanced towards the beginning of the track when it is transported away from the medium source by the internal conveyer.
The guide of the internal medium conveyer preferably cooperates with a second guide in order to direct the band-shaped medium in the desired direction. The second guide can be mechanically connected, for example, with the first holding mechanism. The second guide especially can be placed at different positions, up the control of the controller. This is further described further below.
The transporting of the band-shaped medium by the internal medium conveyor from the medium source through the track opening and through the second holding mechanism allows for an automatic loading of the clamping arrangement in that the second holding mechanism clamps the band-shaped medium while the clamping arrangement is rotated. During the rotation, the band-shaped medium is conveyed from the medium source by the internal medium conveyor. The band-shaped medium is thereby again preferably at least about parallel to the axis of rotation. The internal medium conveyor and the second holding mechanism are correspondingly constructed therefor.
The rotation preferably ends when the track end has reached the preselected position relative to the second holding mechanism. The first holding mechanism is also preferably located at this track end. In this first preselected position, the transfer of the band-shaped medium guided along the clamping track from the second holding mechanism which still holds the band-shaped medium (front end of the band-shaped medium) to the first holding mechanism can then take place. In this position, the band-shaped medium extends from the medium source through the internal medium conveyor to the beginning of the track, along the clamping track, and beyond the end of the track to the second holding mechanism. The control is constructed such that it causes the transfer of the band-shaped medium from the second holding mechanism to the first holding mechanism. The second holding mechanism is therefor actuated to release the held band-shaped medium and the transport mechanism is actuated to reverse transport the band-shaped medium (the front end of the band-shaped medium) against the medium supply direction so that -the front end approaches the first holding mechanism.
Once the band-shaped medium, especially the front end of the band-shaped medium is in the vicinity of the first holding mechanism, the first holding mechanism is actuated to capture the front end. The front end of the band-shaped medium is herefor first preferably transported against the supply direction by the transport mechanism and past the first holding mechanism. The first holding mechanism is then opened (second loading position), so that it can receive the front end. The band-shaped medium is subsequently again advanced in supply direction until the front end of the band-shaped medium can be captured by the first holding mechanism. The first holding mechanism is then closed (first loading position) to hold the front end of the band-shaped medium.
When the band-shaped medium, especially its front end, is held by the first holding mechanism at the end of the track, the band-shaped medium is transported by the transport mechanism and/or the internal medium conveyor in reverse of the band-shaped medium supply direction to tighten the band-shaped medium along the clamping track.
When the band-shaped medium is transferred from the internal medium conveyor to the second holding mechanism, the clamping arrangement takes up a similar rotational position as when the band-shaped medium is transferred from the second holding mechanism to the first holding mechanism. Thus, the first preselected position preferably corresponds with the second preselected position in such a way that for the loading of the clamping track with the band-shaped medium the clamping arrangement carries out about one full rotation or more.
Once the band-shaped medium is taut on the clamping arrangement, the recording of the images on the band-shaped medium is carried out by way of the at least one recording apparatus. The clamping arrangement is preferably rotated herefor while the at least one recording apparatus remains stationary. A complete revolution of the band-shaped medium is again preferably carried out herefor. This rotation is not impeded by the transport mechanism since the latter is actuated by the control to be out of contact with the band-shaped medium during the recording process and the rotation required therefor. Once a number of complete rotations has been carried out or a number of rotations were carried out until the clamping arrangement is again in the first preselected position, and if the recording is complete, a transfer of the band-shaped medium is carried out, especially the front end of the band-shaped medium, from the first to the second holding mechanism by way of the control for the unloading of the band-shaped medium provided with the images from the clamping arrangement. Several rotations are preferably carried out for the recording process, for example, for a line-by-line recording.
For the transfer from the first holding mechanism to the second holding mechanism, the transport mechanism is again brought into contact with the band-shaped medium and the first holding mechanism is opened in order to release the front end of the band-shaped medium. The band-shaped medium is then transported by way of the transport mechanism from the first holding mechanism to the second holding mechanism. This is preferably supported by a guide which may correspond with the rear surface of the already above-mentioned further guide. This guide is then preferably moved into an active position in which it guides the band-shaped medium from the first holding mechanism to the second holding mechanism when the first holding mechanism is opened.
A cutting device is preferably provided which severs the band-shaped medium when it has been conveyed or unloaded from the clamping arrangement for a preselected length. The cutting device is preferably mechanically connected with the clamping arrangement and thus rotates therewith. However, it can also be mounted stationary. In order to unload the band-shaped medium for the preselected length, the second holding mechanism is preferably also constructed for a conveying of the band. For example, it can be provided with a part of rollers between which the band is held when the rollers are not rotated and conveyed when the rollers are rotated.
The first holding mechanism preferably includes the cutting device (first cutting device) and/or is mechanically coupled therewith. A mechanic coupling is preferably achieved in such a way that the band-shaped medium is severed when the first holding mechanism is moved from the open position (second loading position) into the closed position (first loading position).
Once the band-shaped medium has been transported off the clamping arrangement for a preselected length for the unloading thereof, it is preferably transferred from the second holding mechanism to a third holding mechanism. A second cutting device is preferably positioned after this third holding mechanism which preferably is also adapted for the conveying of the band-shaped medium. The second cutting device is used for dividing the band-shaped medium into subsections which preferably respectively include one picture. The severing by way of the second cutting device is preferably carried out only when the first cutting device has already severed the band-shaped medium. A further transport of the (severed) band-shaped medium from the third holding mechanism to the second cutting device is also preferably carried out only then. The second and third holding mechanisms are preferably spaced from one another in such a way that a loop of the band-shaped medium is formed therebetween before the (severed) band-shaped medium is fully transported from the third holding mechanism to the second cutting device. In other words, the distance between the second and third holding mechanisms is preferably shorter than the length of the severed band-shaped medium (for example less than xc2xd, xc2xc or {fraction (1/10)} of the length), which at least about corresponds with the length of the clamping track. An especially compact recording device can be achieved in this manner.
The first holding mechanism can preferably be brought into a position (first loading position) in which it does not interfere with the transfer between the first holding mechanism and the second holding mechanism. This is advantageous especially during the loading of the clamping arrangement. The first holding mechanism is therefor preferably displaced so that it does not protrude into the conveyance track between the first holding mechanism and the second holding mechanism. Especially preferably, the first holding mechanism is reset into the clamping arrangement, especially the clamping drum.
The first holding mechanism is preferably constructed such that the band-shaped medium can be transported through the first holding mechanism in an open condition thereof (second loading position). For example the band-shaped medium is transported between two clamping jaws of the holding mechanism. The first and second loading positions are preferably selected such that the band material can be conveyed along the same transport track during the transfer between the first and the second holding mechanism.
The first holding mechanism preferably is displaceable in such a way that the band-shaped medium (in the first loading position) can be transported past the first holding mechanism without being transported through the first holding mechanism, for example without being transported between the clamping jaws. In other words, the first holding mechanism can be displaced in such a way that a transport of the front end of the band-shaped medium, which is located off the input side of the first holding mechanism, is possible without the front end of the band-shaped medium entering the capturing region of the first holding mechanism. Thus, in this so called first loading position of the holding mechanism, the front end of the band-shaped medium can be transported from the clamping arrangement, especially from the track end of the clamping arrangement, to the second holding mechanism without interference by the first holding mechanism, for example by the clamping jaws. Interference with the transport results especially in kinking or deflection of the band-shaped medium during the further transport due to the undesired contact with the first holding mechanism or in an upsetting of the band-shaped medium. The second holding mechanism is preferably also positioned relative to the first holding mechanism so that such interference is impossible.
When the first holding mechanism is in the first loading position for the loading of the clamping arrangement, for example, reset, the controlled transport direction of the band-shaped medium is preferably reversed, just as when the first holding mechanism is opened for the unloading of the clamping arrangement and the band-shaped medium is transported in such a way that it can be captured by the first holding mechanism, i.e. transported, for example, between two clamping jaws.
In a first preferred embodiment, the first loading position corresponds with the clamping position or holding position of the first holding mechanism. For example, when the first holding mechanism is in the clamping position, the band-shaped medium is held by the inner surfaces of the two clamping jaws. If it is in the first loading position, which corresponds with the clamping position, the band-shaped medium is guided along the backside of that clamping jaw which is closer to the transport mechanism.
The open position of the first holding mechanism in which the band-shaped medium can be transported to the first holding mechanism for clamping or in which at the beginning of the unloading the first holding mechanism can release the band-shaped medium, is herein referred to as second loading position. As already mentioned above, the first holding mechanism is preferably moved to the first loading position for the loading during the transfer between the first holding mechanism and the second mechanism so that the second loading position can be freely structured. It is preferably structured in such a way that in the second loading position a transport (in opposite direction) is carried out between the first holding mechanism and the second holding mechanism for the unloading along the same conveying path.
The transport mechanisms and the first holding mechanisms are preferably coupled with one another either mechanically (for example by way of control disks) and/or electrically (for example by way of an electric control and step motors). The coupling is preferably in such a manner that in a first coupled position, the first holding mechanism is in the first loading position and thus allows a free transfer, and the transport mechanism does not contact a band-shaped medium on the clamping track. When the first loading position corresponds with a clamping position of the first holding mechanism, which is preferably the case, a band can be tightened along the clamping track from the first holding mechanism to the beginning of the track in the first coupled position. Since the transport mechanism is not in contact with the clamping track, the tightened band-shaped medium can be freely rotated in the first coupled position, for example to carry out a recording. In the first coupled position, the clamping arrangement can also be moved into that position (second preselected position) in which the band-shaped medium can be transported from the internal medium conveyor to the second holding mechanism. The first coupled position is thereby suited as starting point for both the loading as well as the unloading (after completely recording) whereby the first coupled position already allows a transport for the loading, while at the beginning of the unloading the band-shaped medium is still held in the first coupled position.
In a second coupled position, the first holding mechanism is in the first loading position, which means it does not impede a transfer (for the loading), and the transport roller is in contact with the band-shaped medium guided along the clamping track (especially in the vicinity of the first holding mechanism). In the second holding position, a transfer from the second holding mechanism to the first holding mechanism can thereby be carried out for the loading by way of the transport mechanism, after the clamping arrangement was freely rotated in the first coupled position while the second holding mechanism holds the band-shaped medium in order to load the clamping arrangement.
The second coupled position also provides a further step for the unloading of a band-shaped medium provided with pictures. While the band-shaped medium is still held during the unloading in the first loading position by the first holding mechanism, the transport mechanism is already brought into contact with the band-shaped medium. The band-shaped medium is thereby held on the clamping track even when in the next step the first holding mechanism is released (second loading position).
In a third coupled position, the first holding mechanism is moved into the second loading position, it is thus released, in order to release a clamped band-shaped medium or to receive a band-shaped medium for holding. During loading, the band-shaped medium is supplied to the first holding mechanism in the third coupled position by the transport mechanism (after it has been guided past the first holding mechanism in opposite direction in the first loading position), so that the first holding mechanism can then hold the band-shaped medium by transfer into the first loading position. For example, this is carried out by shifting from the first coupled position into the second coupled position and then into the first coupled position in which finally the recording of the images can be carried out.
The third coupled position also initiates the end of the unloading process. The first holding mechanism in the second loading position releases the held band-shaped medium which can then be transported to the second holding mechanism by way of the transport mechanism. In contrast to the unloading, the transport is thereby not carried out past the first holding mechanism but through the capturing region of the first holding mechanism. When the first holding mechanism is coupled with a (first) cutting device, as discussed above, the band-shaped medium can be severed simply by closing of the first holding mechanism or shifting thereof into the first position, after it has been unloaded. This is carried out preferably by shifting from the third coupled position through the second coupled position into the first coupled position.
In accordance with the invention, the sequence of the first, then the second and finally the third coupled position (and the subsequent reverse sequence) provides for the achievement of an automatic loading process as well as an automatic unloading process, when the control arrangement respectively suitably carries out the transport processes, depending on the coupled positions as described above.